How do you solve the equation by factoring and the zero-product rule: #4x^2-25#?

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Answer 1 · 2016-12-06T18:26:51

#+-5/2#

Method 1

#4x^2-25=0#

factorise by difference of squares

#(2x+5)(2x-5)=0#

solving for each bracket

#2x+5=0=>2x=-5=>x=-5/2#

#2x5=0=>2x=5=>x=5/2#

Method 2

rearrange the eqn for #""x#

#4x^2-25=0=>4x^2=25#

#x^2=25/4#

#x=+-sqrt(25/4)=+-5/2#